Many bow sight designs and configurations are known. Bow sights generally have multiple sight points for shooting arrows at targets positioned at different distances from the archer. Many bow sights include multiple sight points attached to horizontal pins; examples of such bow sights are shown, for example, in U.S. Pat. Nos. 5,103,568; 5,676,122; and 5,685,081. A more recent development has been a bow sight with vertical pins. An example of a bow sight having vertical pins and a fiber optic sight point at the end of the pins is shown, for example, in U.S. Pat. No. 6,418,633. A number of U.S. patents disclose bow sights having various other arrangements of sight points. See, for example, U.S. Pat. Nos. 3,234,651; 4,120,096; 5,086,567; and 5,131,153.
Bow sights have typically been designed to provide accurate sighting over changing distances where the elevation difference between the target and the shooter remains relatively constant. In other words, the position of each sight point is adjusted to effectively target an object at a set distance measured from the shooter while the vertical displacement, or elevation, between the shooter and the target is assumed to be constant. As such, if a bow having sight points adjusted to be accurate over level ground is used to shoot at a target located either above or below the shooter, the resulting shot will be off target. For example, if the target is below the shooter, the sight will overcompensate for the arrow drop due to gravity and the shot will be too high.
To ensure accuracy, traditional sight points require recalibration and manual readjustment whenever the relative elevation difference between the shooter and the target is varied. Pendulum style bow sites have been developed that automatically adjust to maintain accuracy when the bow is used to shoot targets located at different elevations relative to the shooter. See, for example, U.S. Pat. Nos. 6,145,208; 5,253,423; and 5,121,547; see also U.S. patent application Ser. No. 10/661,918 filed Sep. 12, 2003, which is incorporated herein by reference. Nonetheless, the current sights in this field can be improved with respect to their accuracy, ease of use, reliability, and simplicity.